In beauty art, it is known that human skins are dipped in moderately hot water and/or a cold water and thereafter massaged whereby relative good massaging effect is attained.
This massaging method, however, is troublesome because of needing somewhat long time for the preparation of hot and cold waters. Further, since the temperature of the hot water is limited to a certain value, that is, room temperature plus 20.degree. C, thermal stimulation obtained by this method is lower than a desired level. If the temperature of the hot water is too high, a woman will suffer from scald.